Vpn for 60 sites

[Meduober]

Our network of 60 remote sites linked to the central office is based on a leased VPN link provided by a telecom operator.

The solution is very costly compared with the bandwidth, which is no more than 0.5 Mb in most sites. we'd like to set up our own Vpn network using Cisco equipment. what do you recommend?

I insist on the traffic security part

Thank you